This invention relates to facsimile transmitters and receivers of the type utilized to transmit and receive information-bearing signals representing dark/light variations on a document located at the transmitter and converting the information-bearing signals to marks or images on a copy medium located at a receiver so as to form a copy which is a reasonable facsimile of the original document.
Most facsimile transmitters and receivers in commercial use at the present time are supplied with document or copy medium sheets by hand. In other words, an operator takes an individual sheet of paper, whether the individual document or a blank piece of copy medium, and places that sheet on or in the scanning means of the transmitter receiver, typically a drum having a clamp for clamping one edge of the sheet. In some facsimile transmitters and receivers, sheet feeding is automated to varying degrees. However, automated sheet feeding becomes difficult where the size of the documents vary from sheet to sheet. In many instances, a variation in sheet to sheet sizes is accommodated by utilizing a document carrier in which the various sized documents are sandwiched. However, the use of a document carrier can be burdensome in many instances.
When a document carrier is not utilized, any nonuniformity of sheet size may create considerable difficulty. One such difficulty can arise when efforts are made to remove the sheet from the scanning means. Where the scanning means comprises a rotatable drum and the sheet is wrapped around the drum, the final position of the drum after scanning becomes important in removing the sheet from the drum. Where the sheet is removed by engaging the sheet adjacent the clamping area of the drum, the drum may be returned to the same position and the sheet may be reliably removed. However, the sheet may not be reliably removed by engaging the trailing edge of the sheet removed from the clamp when the drum is returned to the same position time after time since the overall length of the sheet around the drum will vary with the sheet size. The position of the means for removing the sheet will not be appropriately located with respect to the trailing edge.